1. Field of the Invention
The present invention relates to a resin-sealed semiconductor device. Specifically, it relates to a resin-sealed semiconductor device whereby a semiconductor chip is electrically connected to leads for external connections by means of electrically conductive materials.
2. Conventional Technology
In resin-sealed semiconductor devices where semiconductor chips are connected electrically to leads for external connections by electrically conductive materials, the semiconductor chip surface PN connectors, MOS gates, bonding pads, and fine aluminum wires, as well as such electrically conductive material as bonding wires, solder bumps, and beam leads have been coated with a hardened silicone layer such as high-purity silicone resin, silicone rubber, or silicone gel, in order to prevent degeneration and corrosion and to moderate mechanical stress and stress due to expansion and contraction accompanying temperature changes in the sealing resin. A coating of sealing resin is then applied over the coating formed by the hardened silicone layer. FIG. 4 shows a cross-sectional diagram of this type of conventional resin-sealed semiconductor device. A portion of the bonding pad (3) and the gold bonding wires (4) are coated with a liquid hardenable silicone rubber composition. This is thermally hardened to form a silicone rubber layer (5). A sealing resin such as the epoxy resin (6) is then used to form a seal over this silicone rubber layer, the remainder of the bonding wires (4), and the inner portion of the lead wires for external connections (7).